We adopt the unimodal audio tracker from the DOAnet architecture [1]}. Here, a multi-channel STFT is performed on the individual microphone signals. Time-frequency analysis is conducted on the 6-channel acoustic inputs using a window length of 1920 samples with no overlap and a FFT size of 2048. This results in a frame length of \(40\,\text{ms}\) , matching the length of one video frame in the utilized dataset. A context of one frame in both temporal directions around the \(t\) -th time step is used, which results in a 3-dimensional acoustic input tensor \(\mathrm {X}_{\text{A}, t}\)  of dimensions \(3 \times 1024 \times 12\) , representing the time, frequency and channel dimensions. The third dimension is spanned by the stacked amplitude and phase of all 6 audio channels.
